You cannot define indexes at object creation. And while a typical table will create an index for a primary key, I suspect that this does not happen for table variables. And in at least SQL 2008, indexes are explicitly NOT supported for table variables (from the link on the post above):

Indexes cannot be created explicitly on table variables, and no statistics are kept on table variables. In some cases, performance may improve by using temporary tables instead, which support indexes and statistics. For more information about temporary tables, see CREATE TABLE (Transact-SQL).

Given this wording, I think that the question is not at all clear what it is intending. The only possible indexes might be a byproduct of primary key creation, and otherwise indexes are NOT supported.